Hooking up an older MacMini to a USB-C KVM Switch

I have an IOGear USB-C based KVM switch that I've been using between my Macbook Air and a Dell Windows laptop. That works fine. But now I have a project where I need to replace the Dell with a Late 2014 MacMini which does not have any USB-C connections. Can that be done? And if so, how? Can I use the Apple USB-C Digital AV Multiport Adapter backwards?